PROJECT SUMMARY Vascular access is a life-line to the health and well-being for patients receiving chronic hemodialysis. A consensus exists arteriovenous fistulas (AVF) is the safest and most effective vascular access for hemodialysis. The implementation of the Fistula First Catheter Last Initiative (FFCLI) has increased fistula use over the last decade. Yet the rise of fistula use has not been universal across race and region of the country. Furthermore, the quality of fistula placement surgery remains poor. Research examining fistula use has focused on `demand side' factor ? patients and their immutable characteristics. Scant research has examined the `supply side' of vascular access placement ? physicians who create and maintain vascular access. Studies on vascular access physicians are important because: (1) the skill of physicians creating and maintaining vascular access is critical to the success of fistula and wellbeing of hemodialysis patients; (2) the skill set, refined by years of specialty training and influenced by their practice setting, may be modifiable; and (3) there are no data relating the supply and professional characteristics of physicians who perform AVF access procedures to geographic/racial variation of vascular access and quality of access. A comprehensive and systematic assessment of the supply and professional attributes of access surgeons and other providers is critically needed in order to inform medical education and physician workforce policy. This R21 proposal seeks to test the feasibility of developing a national registry to link the supply and professional characteristics of physicians who create and maintain AVF with the geographic/demographic variation and outcomes of AVF use.